Lifts are used to access the underside of vehicles for maintenance purposes. For example, in a car or truck, the engine oil can be changed only from beneath the vehicle. It is much more convenient to raise the vehicle up so as to allow maintenance personnel to walk, rather than crawl, under the vehicle.
The vehicle is driven onto the lift. Lifting members engage the vehicle chassis. The lift is then actuated, wherein the vehicle is raised to a desirable height. Once the vehicle is positioned up off of the ground, a mechanic can then access the underside of the vehicle.
In the prior art, there are various types of lifts. One type is located in the ground. This type of lift includes a cylinder that supports the lifting members. The cylinder rises out of the ground and lowers back into the ground. This type of lift is expensive to install, as it requires excavation and other below ground work.
Another type of lift utilizes fixed vertical posts. The posts are mounted above ground, and consequently are less expensive to install than the below ground type of lift. Lifting members traverse the posts up and down to lift the vehicle. These post type of lifts come in four post or two post varieties.
Conventional four post lifts utilize four posts, with each post positioned at a comer of a rectangular area. The vehicle is driven onto ramps that are located between the posts. The ramps are raised and lowered along the posts.
Conventional two post lifts have been used in the automotive industry for some time. The two posts are spaced apart from each other. The vehicle is driven to a location between the posts. Each post has two pivotable lifting arms that move inward toward the vehicle. One lifting arm engages the front portion of the vehicle, while the other lifting arm engages the rear portion. The lifting arms can telescope to vary their length. By swinging and adjusting the length, each lifting arm can be positioned under an appropriate lifting point of the vehicle chassis.
Recently two post lifts and four post lifts have been used for turf equipment. Such turf equipment includes walk behind mowers and riding mowers. Beattie, et al., U.S. Pat. No. 5,211,264 shows one such lift. Golf courses especially use turf equipment that require frequent maintenance. For instance, mowers have reel cutters that must be cleaned and sharpened.
Such turf equipment may have 2, 3, or 4 wheels and a shortened wheel base between the front and rear axles. Raising turf equipment with a four post lift merely requires driving the turf equipment onto the ramps. The ramps may have to be repositioned in order to accommodate the distance between the wheels.
However, with a two post lift, it is difficult to position conventional lifting arms under turf equipment so that the lifting arms engage the equipment properly. In addition, many lift owners wish to use their two post lift for raising both road vehicles, such as cars and trucks, as well as turf equipment. Such dual use eliminates the need to buy two lifts, one lift for road vehicles and the other lift for turf equipment. In addition, one lift takes up less floor space than does two lifts. In fact, a two post lift takes up less floor space than a four post lift. Therefore, many lift owners prefer a two post lift over a four post lift.
The lift shown in U.S. Pat. No. 5,211,264 is not suitable for lifting road vehicles. This is because the lifting arms are designed to raise small vehicles such as turf equipment.
What is needed is a lift that can be easily adapted to raise both road vehicles and smaller vehicles such as turf equipment.